/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.attribute.annotation.visitor;

import proguard.classfile.*;
import proguard.classfile.attribute.CodeAttribute;
import proguard.util.*;

import java.util.List;

import a.annotation.proguard.classfile.attribute.annotation.Annotation;

/**
 * This <code>AnnotationVisitor</code> delegates its visits to another given <code>AnnotationVisitor</code>, but only
 * when the visited annotation has a type that matches a given regular expression.
 *
 * @author Eric Lafortune
 */
public class AnnotationTypeFilter implements AnnotationVisitor {
    private final StringMatcher regularExpressionMatcher;
    private final AnnotationVisitor annotationVisitor;

    /**
     * Creates a new AnnotationTypeFilter.
     * 
     * @param regularExpression the regular expression against which annotation type names will be matched.
     * @param annotationVisitor the annotation visitor to which visits will be delegated.
     */
    public AnnotationTypeFilter(String regularExpression, AnnotationVisitor annotationVisitor) {
        this(regularExpression, null, annotationVisitor);
    }

    /**
     * Creates a new AnnotationTypeFilter.
     * 
     * @param regularExpression the regular expression against which annotation type names will be matched.
     * @param variableStringMatchers an optional mutable list of VariableStringMatcher instances that match the
     *        wildcards.
     * @param annotationVisitor the annotation visitor to which visits will be delegated.
     */
    public AnnotationTypeFilter(String regularExpression, List variableStringMatchers,
        AnnotationVisitor annotationVisitor) {
        this(new ListParser(new ClassNameParser()).parse(regularExpression), annotationVisitor);
    }

    /**
     * Creates a new AnnotationTypeFilter.
     * 
     * @param regularExpressionMatcher the string matcher against which class names will be matched.
     * @param annotationVisitor the annotation visitor to which visits will be delegated.
     */
    public AnnotationTypeFilter(StringMatcher regularExpressionMatcher, AnnotationVisitor annotationVisitor) {
        this.regularExpressionMatcher = regularExpressionMatcher;
        this.annotationVisitor = annotationVisitor;
    }

    // Implementations for AnnotationVisitor.

    public void visitAnnotation(Clazz clazz, Annotation annotation) {
        if (accepted(annotation.getType(clazz))) {
            annotationVisitor.visitAnnotation(clazz, annotation);
        }
    }

    public void visitAnnotation(Clazz clazz, Field field, Annotation annotation) {
        if (accepted(annotation.getType(clazz))) {
            annotationVisitor.visitAnnotation(clazz, field, annotation);
        }
    }

    public void visitAnnotation(Clazz clazz, Method method, Annotation annotation) {
        if (accepted(annotation.getType(clazz))) {
            annotationVisitor.visitAnnotation(clazz, method, annotation);
        }
    }

    public void visitAnnotation(Clazz clazz, Method method, int parameterIndex, Annotation annotation) {
        if (accepted(annotation.getType(clazz))) {
            annotationVisitor.visitAnnotation(clazz, method, parameterIndex, annotation);
        }
    }

    public void visitAnnotation(Clazz clazz, Method method, CodeAttribute codeAttribute, Annotation annotation) {
        if (accepted(annotation.getType(clazz))) {
            annotationVisitor.visitAnnotation(clazz, method, codeAttribute, annotation);
        }
    }

    // Small utility methods.

    private boolean accepted(String name) {
        return regularExpressionMatcher.matches(name);
    }
}
